I. Field of the Invention
The present invention is directed primarily to truck bodies designed specifically for refuse hauling and, more particularly, to replaceable wear shoes for use with reciprocating mechanisms associated with the packing or ejecting systems of such vehicles.
II. Related Art
Refuse hauling trucks commonly include a truck body specifically designed for receiving, compacting, storing and discharging refuse materials and typically include all of the associated operating mechanisms. Mechanized packer and ejector systems are utilized on such truck bodies in the compacting of the refuse within the truck body and subsequent discharge of stored refuse from the truck body. Successful types of refuse processing vehicles include front or side loading vehicles in which the materials are loaded from the front or side of the vehicle into a charging or receiving hopper behind the cab thereafter processed rearward into a storage body by a rearward moving packer mechanism. Full reservoirs are emptied by or discharged through a rear door, the truck body typically being tilted to empty the contents. When closed, the door serves as the back wall of the storage compartment against which the material is packed. In certain embodiments, the packer mechanism may also aid in pushing the compacted material toward discharge from the rear of the storage compartment.
Rear-loading refuse handling truck bodies typically include a refuse handling reservoir designed for both loading and discharging from the rear of the vehicle. These truck bodies also include a rather large tailgate section that carries the receiving hopper portion and the compacting or packing mechanism. The blade packing mechanism includes a vertically pivoting hydraulic packer which operates to sweep material forward from the tailgate loading area. The packer operates together with and is rotatably attached to the lower end of a sliding storage compartment rear closing door or "slide" system. The compacting or packer system includes a hydraulic cylinder operating the rotating packer blade which operates repeatedly to compact refuse in a forward direction beneath and in front of the sliding door system each time sufficient refuse is loaded by hand or cart tipper into the rear of the tailgate section. After the packing stroke, the packer blade is rotated back to a position substantially parallel to the slide and the slide is retracted to again expose the loading area of the rear portion of the tailgate volume. In this manner, the slide reciprocates carrying the packing mechanism in association with each compaction operation.
The slide system also is supported in the recessed guides by wear shoes which have wear surfaces contacting the top and bottom of the recessed track carrying the slide mechanism and packer. Typically, two spaced shoes are bolted on either side of the slide system and a total of four shoes carry the slide in operation. No access is provided other than from inside the tailgate frame.
The slide system is also operated by a pair of hydraulic slide cylinders as it reciprocates supported along the pair of spaced parallel slide tracks or slide guides in the side walls of the tailgate such that the slide system reciprocates along a path at an acute angle with the plane of the vehicle.
The rear-loader also includes a reciprocating rail mounted blade-type ejector system against which the refuse is compacted and which is also cylinder operated to move forward and aft, on a horizontal plane, in the matter of a plow blade. A hydraulic cylinder, normally of the telescoping variety, mounted on the truck chassis just behind the cab is designed to be connected between the truck chassis and the ejector. The refuse is packed against the ejector incrementally by the hydraulic compacting mechanism cooperating with the slide closer system forcing the ejector forward in the truck body ahead of the compacting refuse until the ejector is fully forward when the storage body is packed to capacity.
In order to discharge the rear-loading truck body, the entire tailgate section of the truck body is unlocked and swung clear of the opening on top-mounted hinges and the ejector operated rearward in a power stroke to expel the entire contents of the refuse storage volume forcibly and without interference. Typically, the bottom portion of the ejector mechanism is supported on a plurality of load bearing sliders or wear shoes that ride in structural guide shapes or rails along which the ejector mechanism slides. These load bearing wear shoes are adapted to support the ejector system just above the truck body floor. With ejectors such as those used in the rear loaders that are supported on load bearing wear shoes, it will be appreciated that the wear shoes undergo a high amount of abrasive wear because of the weight and repeated reciprocal movement of the mechanism and the erosive and corrosive nature of many of the materials processed.
It will be appreciated that the wear shoes carrying both the ejector mechanism and the slide mechanism in a rear-loading packer are subject to a high degree of wear. Shoes of the class that provide bearing surfaces for most ejectors, slides and reciprocating packer systems wear rapidly and must be replaced on a frequent basis as part of normal maintenance. Replacement of the shoes can be a difficult and time consuming project and this is particularly true with respect to the slide wear shoes associated with rear-loading packers. The shoes are typically bolted on to the outside of the slide assembly and, since they are carried in recesses in the side of the tailgate, access to the bolts is extremely difficult from a maintenance standpoint. In addition, the shoe surfaces and, of course, the bolts are exposed to corrosive and oxidizing refuse materials which tend to cause rapid corrosion, thereby increasing the difficulty of removal.
Time consuming maintenance items represent serious drawbacks with respect to the operating costs and desirability of particular refuse collection vehicles and innovations which reduce necessary scheduled maintenance costs represent significant advances in the art. Reducing the frequency and time required to renew wear shoes particularly slide shoes in rear-loading refuse bodies would be a much desired improvement.
Accordingly, it is a primary object of the present invention to provide a wear shoe system that significantly reduces the frequency and complexity of replacement.
Another object of the present invention is to provide a replaceable wear shoe system that reduces corrosion and increases wear shoe life.
Yet another object of the present invention is to provide a replaceable wear shoe system that eliminates the need for bolting the shoes in place.
Still another object of the present invention is to provide a relatively lightweight, less expensive wear shoe in which upper and lower high wearing, low friction slide surfaces are spaced by less expensive, relatively lightweight filler material.
Other objects and advantages become apparent to those skilled in the art upon further familiarization with the specification, drawings and appended claims contained herein.